Answer:
C. 5.6 × 10^11 N/C
Explanation:
The electric field
at a distance
from a charge
is given by

where
is the coulomb's constant.
Now, in our case

;
therefore,


which is choice C from the options given<em> (at least it resembles it).</em>
<u>Answer:</u>
The height of ramp = 124.694 m
<u>Explanation:</u>
Using second equation of motion,

From the question,
u = 31 m/s; s = 156.3 m, a=0
substituting values

t = 
= 5.042 s
Similary, for the case of landing
t = 5.042 s; initial velocity, u =0
acceleration = acceleration due to gravity, g = 9.81 
Substituting in 

h = 124.694 m
So height of ramp = 124.694 m
Explanation:
The given data is as follows.


Electric potential energy (
) = ?
Formula to calculate electric potential energy is as follows.
= 
= 
Thus, we can conclude that the electric potential energy of the pair of charges when the second charge is at point b is
.
Explanation:
Newton's second law:
∑F = ma
277 N − 245 N = (25 kg) a
a = 1.28 m/s²